Soldering alloy



lent soldering properties:

' Patented Mar. 3, 1942 No Drawing. A'pplicationJanuary 27, 1941, Se-

rial No. 376,196. In Germany November 5,

2 Claims. ,(Cl. 75-165) The present invention relates to tarnishresistant soldering alloys which are of yellowish color and areparticularly suitable for soldering I yellow gold alloys.

This applicationis a continuation-in-part of my co-pending applicationSerial No, 238,064, filed October 31, 1938. x

It is the object of the present invention to provide alloys whichpossess the necessary prop-' erties for soldering, for example, a lowmelting point, easy fusibility, resistance against tarnishing,.'capacity for rolling and compatibility with I In accordance with thepresent invention it has been found that the tarnish resistant, yellowalloys of the following composition possess excel- Per cent Gold 25-85Palladium g 2-20 Copper 5-30 Cadmium 3-25 Silver 0.5

Preferably the alloys are of the following composition;

Per cent Gold 7 -70 Palladium 5-10 Copper 10-25 Cadmium 3-25 Silver 5-10Small quantities of other'metals, either alone or in combination, may beadded to influence the qualities of the solder in accordance with thepresent invention to a certain extent. The quantity' of the added metalsshould, in general, however, not exceed about 5%, preferably 4%. Theaddition of small quantities of zinc, for example,

about 0.1% to 2.5%, produces more dense cast- Examples 10- Melting Pd AuAg Cu Zn Cd point interval Degrees so 550 120 150 875-795 15 100 550 120150 2o 160 910-825 s 100 550 150 10 so 9oo-sao so @o 100 10 140 535-75050 650 20 10 795-720 so 100 so 100 10 so 885-780 so 700 100 50 1o 90925-190 50 480 200 10 100 soo-7oo so 315 200 205 10 695-630 20 v Thesoldering alloys in. accordance with the present invention may beemployed for many quantities of agents having a deoxidizing action tothe alloy. Examples of suitable deoxidizing agents are as follows:titanium, silicon, magnesium and calcium boride. The following are anumber of examples of soldering alloys in accordance with the presentinvention: I a

purposes and are especially suitable for soldering yellow-gold alloys asthey are of yellowish color.

While I have described herein some embodi-' ments of my invention, Iwish it to be known that I do not intend to limit myself thereby,

except within the scope of the appended claims.

ings, "and the addition of small quantities of manganese, for exampleabout 0.03% to 0.6%

improves the rolling capacity of the soldering alloy; Addition of bothmetals in the proportions stated will improve the soldering alloy inboth directions. Also it is possible to add small Iclaimz- 1. Asoldering alloy highly resistant against tarnishing essentiallycomprising 25% to 85% of gold, 2% to 20% of palladium, 5% to 30%-ofcopper, 3% to 25% of cadmium, 0.5% to 20% of silver, and 0.1% 105% ofzinc, said gold, pal1a-' dium, copper, cadmium, silver andzincconstituting substantially all of the alloy.

2. A soldering alloy highly resistant against tarnishing essentiallyc'omprising'50% 'to-'70% or gold, 5% to 10% of palladium, 10% to 25% ofcopper, 3% to 25% of cadmium, 0.5% to 10% of silver and 0.1% to 2.5% ofzinc, said gold, palladium, copper, cadmium, silver and zincconstituting substantially all of thealloy.

J O SEF LEUSER.

